Closed loop energy systems may be used for emitting energy from a source of energy and for detecting data transmitted to a detector. The term “detect” with respect to energy systems, radiation, information, images and methods, as used herein means read or receive or gather energy directly or indirectly from the source in a form that can be used or processed.
Such systems may be radiation systems, in which energy travels through a medium or through space, to be received by another body (including a detector). The energy system may be ionizing or non-ionizing, and may be optical, in which the source of energy is a light source, or may include other energy sources such as may be used in radar or sonar or x-ray or other systems. Optical systems for detecting information that may be encoded are widely used in a variety of known applications, and the method according to this invention will be summarized and described primarily as used in such optical systems. However, the method according to this invention may be used in any other suitable energy system.
One such optical system is a bar code reader system. In this application, encoded information may be provided in indicia which may include a combination of light and dark markings or zones. The markings may be arranged in a bar like pattern that may be called a bar code. The pattern may be associated with nearly any type of object and may encode nearly any type of information. An energy source such as a light source may illuminate the bar code, and a detector may detect reflected light from the bar code to detect the pattern and its encoded information.
Another such optical system may be a position detecting system that detects the position of an object. A position detecting system that detects the position of an object such as a fluid cylinder is shown in U.S. Pat. No. 7,047,865. The cylinder illustrated in that patent includes a piston and a piston rod. Fluid pressure acts against the piston to create a force that causes motion of the piston and piston rod. Encoded information concerning the position of the piston rod may be provided in Indicia which may be a combination of light and dark markings associated with the piston rod. Known optical sensors may include a light source that illuminates the markings and a detector that detects reflected light from the markings. The optical system may determine the position of the piston rod based upon the detected markings and their encoded information.